In recent years, dielectric barrier discharge ionization detectors (which are hereinafter abbreviated as the “BIDs”) employing the ionization by dielectric barrier discharge plasma have been put to practical use as a new type of detector for GC (for example, see Patent Literatures 1 and 2 as well as Non Patent Literature 1).
BIDs described in the aforementioned documents are roughly composed of a discharging section and a charge-collecting section which is located below the discharging section. In the discharging section, a low-frequency AC high voltage is applied to a plurality of plasma generation electrodes circumferentially formed on the outer wall of a tube made of a dielectric material, such as quartz glass (“dielectric tube”), to ionize an inert gas (plasma generation gas) supplied into the tube line of the dielectric tube and thereby form atmospheric-pressure non-equilibrium plasma. Due to the effects of the light emitted from this plasma (vacuum ultraviolet light), excited species and other elements, the sample components in a sample gas introduced into the charge-collecting section are ionized. The resulting ions are collected through a collecting electrode provided in the charge-collecting section, to generate detection signals corresponding to the amount of ions, i.e. the amount of sample components.